Methods of epitaxially growing boron-containing structures

Abstract

Embodiments of the present invention generally relate to methods of epitaxially growing boron-containing structures. In an embodiment, a method of depositing a structure comprising boron and a Group IV element on a substrate is provided. The method includes heating the substrate at a temperature of about 300° C. or more within a chamber, the substrate having a dielectric material and a single crystal formed thereon. The method further includes flowing a first process gas and a second process gas into the chamber, wherein: the first process gas comprises at least one boron-containing gas comprising a haloborane; and the second process gas comprises at least one Group IV element-containing gas. The method further includes exposing the substrate to the first and second process gases to epitaxially and selectively deposit the structure comprising boron and the Group IV element on the single crystal.

What is claimed is: 
     
         1 . A method of depositing a structure on a substrate, the method comprising:
 flowing a first process gas and a second process gas into a substrate processing chamber, wherein:
 the substrate is positioned within the substrate processing chamber, the substrate has a dielectric material and a crystalline material formed thereon, and the crystalline material comprises a Group IV element; 
 the first process gas comprises diborane (B 2 H 6 ) and boron trichloride (BCl 3 ), and the BCl 3  flows at a flow rate within a range of 1 sccm to 100 sccm, and 
 the second process gas comprises at least one Group IV element-containing gas; and 
   exposing the substrate to the first process gas and the second process gas to epitaxially and selectively deposit the structure comprising boron and the Group IV element on the crystalline material, the structure having a boron concentration of 5×10 20  atoms/cm 3  or more.   
     
     
         2 . The method of  claim 1 , wherein the boron concentration is 1×10 21  or more. 
     
     
         3 . The method of  claim 1 , wherein the first process gas and the second process gas selectively deposit the structure at a growth rate of 100 Å/min or more. 
     
     
         4 . The method of  claim 1 , further comprising heating the substrate to a temperature of 300° C. or more. 
     
     
         5 . The method of  claim 1 , wherein the flow rate of the BCl 3  is within a range of 1 sccm to 30 sccm. 
     
     
         6 . The method of  claim 5 , wherein the flow rate of the BCl 3  is within a range of 1 sccm to 10 sccm. 
     
     
         7 . The method of  claim 1 , wherein the first process gas is flown into the substrate processing chamber and is exposed to the substrate prior to flowing the second process gas into the substrate processing chamber. 
     
     
         8 . The method of  claim 1 , further comprising co-flowing the first process gas and the second process gas into the substrate processing chamber after exposing the substrate to the first process gas. 
     
     
         9 . The method of  claim 1 , wherein the second process gas comprises Si, Ge, or a combination thereof. 
     
     
         10 . The method of  claim 1 , wherein the first process gas further comprises one or more of: borane (BH 3 ), triborane (B 3 H5), tetraborane (B 4 H 10 ), pentaborane (9) (B 5 H 9 ), pentaborane (11) (B 5 H 11 ), hexaborane (10) (B 6 H 10 ), hexaborane (12) (B 6 H 12 ), decaborane (14) (B 10 H 14 ), trimethylborane ((CH 3 ) 3 B), dimethylborane ((CH 3 ) 2 BH), triethylborane ((CH 3 CH 2 ) 3 B), diethylborane ((CH 3 CH 2 ) 2 BH), tripropylborane ((CH 3 CH 2 CH 2 ) 3 B), or tributylborane ([CH 3  (CH 2 ) 3 ] 3 B), triphenylborane ((C 6 H 5 ) 3 B). 
     
     
         11 . The method of  claim 1 , wherein the structure has an amount of germanium (Ge) that is from 10 atomic % to 70 atomic %. 
     
     
         12 . A method of growing a structure on a substrate, the method comprising:
 heating the substrate at a temperature of 300° C. to 700° C., the substrate positioned within a substrate processing chamber, the substrate having a dielectric material and a single crystal formed thereon, and the single crystal comprising Si, Ge, or a combination thereof; and   epitaxially and selectively growing the structure on the single crystal, the structures comprising boron and a Group IV element, and the growing comprising:
 flowing a first process gas, a second process gas, and a carrier gas into the substrate processing chamber, wherein:
 the first process gas comprises diborane (B 2 H 6 ) and boron trichloride (BCl 3 ), 
 the second process gas comprises at least one Group IV element-containing gas, and 
 the carrier gas comprises H 2 , N 2 , or a combination thereof; and 
 
 exposing the substrate to the first process gas and the second process gas to epitaxially and selectively grow the structure, the structure having a boron concentration of 5×10 20  atoms/cm 3  or more. 
   
     
     
         13 . The method of  claim 12 , wherein the BCl 3  flows at a flow rate within a range of 1 sccm to 100 sccm, and the first process gas and the second process gas selectively deposit the structure at a growth rate of 100 Å/min or more. 
     
     
         14 . The method of  claim 12 , wherein:
 n is 0; and   each X is, independently, Cl or Br.   
     
     
         15 . The method of  claim 12 , wherein the first process gas further comprises one or more of: borane (BH 3 ), triborane (B 3 H 5 ), tetraborane (B 4 H 10 ), pentaborane (9) (B 5 H 9 ), pentaborane (11) (B 5 H 11 ), hexaborane (10) (B 6 H 10 ), hexaborane (12) (B 6 H 12 ), or decaborane (14) (B 10 H 14 ). 
     
     
         16 . The method of  claim 12 , wherein the at least one Group IV element-containing gas has the formula: 
       
         
           
           
               
               
           
         
         wherein:
 each of M 1  and M 2  is, independently, Si or Ge; 
 each R 3  is, independently, a halogen or a C 1 -C 6  alkyl group; 
 x is 1, 2, 3, or 4; 
 y is 1, 2, 3, or 4; and 
 z is 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. 
 
       
     
     
         17 . The method of  claim 12 , wherein the at least one Group IV element-containing gas comprises a silane, a germane, or a combination thereof having the formula: 
       
         
           
           
               
               
           
         
         wherein:
 M 1  is Si or Ge; and 
 x is 1, 2, 3, or 4. 
 
       
     
     
         18 . The method of  claim 12 , wherein the first process gas is flown into the substrate processing chamber and is exposed to the substrate prior to flowing the second process gas into the substrate processing chamber, and the method further comprises
 co-flowing the first process gas and the second process gas into the substrate processing chamber after flowing the first process gas into the substrate processing chamber and exposing the first process gas to the substrate.   
     
     
         19 . A method for growing a structure on a substrate, the method comprising:
 epitaxially and selectively growing the structure on the substrate positioned within a substrate processing chamber, the substrate having a dielectric material, the structure comprising boron and the Group IV element, and the growing comprising:
 flowing a first boron-containing gas into the substrate processing chamber, the first boron-containing gas comprising diborane (B 2 H 6 ) and boron trichloride (BCl 3 ), the BCl 3  flowing at a flow rate within a range of 1 sccm to 100 sccm; 
 exposing the substrate with the first boron-containing gas; 
 co-flowing a second boron-containing gas and at least one Group IV element-containing gas into the substrate processing chamber, the first boron-containing gas and the second boron-containing gas being the same or different; and 
 exposing the substrate with the second boron-containing gas and the Group IV element-containing gas to epitaxially and selectively grow the structure, the structure having a boron concentration of about 5×10 20  atoms/cm 3  or more. 
   
     
     
         20 . The method of  claim 19 , wherein the first boron-containing gas is flown into the substrate processing chamber and is exposed to the substrate prior to co-flowing the second boron-containing gas and the at least one Group IV element-containing gas into the substrate processing chamber.